Device for stacking series-connected impedance units



Nov. 25, 1958 DEVICE FOR STACKING SERIES-CONNECTED IMPEDENCE UNITS E. NILSSON Filed July '7, 1955 Fzg3-2 INVENTOR. lfland NcZ 550/1 United States Patent DEVICE FOR STACKING SERIES-CONNECTED IMPEDANCE UNITS Erland Nilsson, Ludvilra, Sweden, assignor to Allminna Svenska Elektriska Aktiebolaget, Vasteras, Sweden, a corporation of Sweden Application July 7, 1955, Serial No. 520,563

Claims priority, application Sweden August 5, 1954 3 Claims. (Cl. 31799) In some electrical apparatus, especially in those designed for high voltage plants, a plurality of impedance units such as capacitors, reactors or resistors is usually connected in series relation. The impedance units may for instance be used for controlling the potential across more or less isolating members. A dividing-up into a plurality of series-connected impedance units is chosen, partly because units manufactured for a lower voltage are safer and cheaper and partly because a plurality of series-connected isolating members sometimes has to be controlled. In this case, each isolating member is conveniently connected in parallel with an impedance unit, which assumes that between the individual impedances terminal devices must be arranged. An example of such an arrangement is the voltage control of the breaking contacts in a high voltage circuit breaker. In parallel with the breaking contacts of the breaker a chain of capacitors or resistors, especially nonlinear resistors, is connected. These impedance units then distribute the voltage across the breaking contacts in a desired manner. The size of the impedance units is determined partly by the current, which will flow through the unit, and partly by the voltage difference existing between the terminals of the unit. For the last-mentioned reason the distance between the terminals cannot be reduced too much, but this distance, in the following called height, is given for impedance units designed for a certain voltage portion. When the individual units are stacked together, an overall height is obtained, which sometimes is larger than the overall height of the members, the potential of which being controlled by the units. question becomes unnecessarily large and expensive.

The present invention eliminates these difiiculties by stacking together the series-connected impedance units in such a heightsaving way that the units are arranged in at least three rows between depressions provided in metallic intermediate plates, the depressions being directed from each other. Figs. 1-3z3 show examples of devices of such a type. Figs. 1 and 2 show schematically the principle for the arrangement, whilst Figs. 3:1, 3:2 and 3:3 show intermediate plates designed according to this principle.

Fig. 1 shows a device, in which impedance units are stacked together with three vertical rows. Fig. 2 shows a device, in which the impedance units are stacked together in four vertical l'oWs. In these two figures, the impedance units, which may be capacitors, reactors or The result is that the apparatus in ICC resistors, designated by 1, are supported between a downward depression 4 and an upward depression 5 in two succeeding intermediate plates 2. The distance between the plates is determined, not only by the impedance units, but also by the spacers 3. In Fig. 2, which shows, as mentioned, a device having the impedance units stacked in four rows, also downward depressions 6 and upward depressions 7 are found with a lower depth than that of the deep depressions 4 and 5. The rows, in which the impedance units are stacked, are indicated by A, B, C and in these schematical drawings. Starting from a certain minimum distance of 1 unit (e. g. 1 mm.) between two succeeding intermediate plates and assuming that the average spacing of the intermediate plates has a value of 2 units, one finds that the overall height of the four series-connected impedance units would have had the value of 4X2:8 units, if the units had been stacked together only in one row. If according to Fig. 1 the stacking together is made in three rows, A, B and C, the totally available height for the impedance units becomes 16 units instead. If the way of stacking according to Fig. 2 is applied, the available overall height instead of it will be 20 units for the four impedance units. As it is seen, the available height of the units thus is increased with the number of rows in the stack provided that, according to the invention, in stacks with more than two rows the depressions in succeeding plates are given a transversal displacement in such a way that a depression in one plate forms, with its concave part, the seat for an impedance unit, while its convex part is directed towards the next intermediate plate, the adjacent surface of which is either substantially plane or has a depression of a depth that is less than that of the former. If instead of the spacing of the plates the overall height of the impedance units is kept constant, a smaller average plate spacingis obtained for a given minimum distance between two plates. The result is that the entire stack gets a lower height.

In Figs. 3:1, 3:2 and 3:3, a form is shown, in which the principle according to Fig. 1 is applied. The figures show the plane view of three succeeding intermediate plates, which are shown as disc-shaped ones. Here the depressions are given a cyclic displacement by angles. In Fig. 3: 1, the downward depression 4 with the impedance unit seated therein is situated in the position A, in Fig. 3:2 in the position B and in Fig. 3:3 in the position C. In these three figure parts, the succeeding intermediate plates are similar to each other. Also in Figs. 3:l-3:3 the spacers 3 have been indicated, which spacers are placed in alignment to each other in adjacent spaces.

The intermediate plates may, of course, have another convenient form than a cylindrical one, and the depressions need not be symmetrical in relation to the plane of the plates. Thus upward depressions may have a height different from that of the downward depressions.

I claim as my invention:

1. A stack device of the character described comprising a plurality of impedance units arranged in axially spaced relation to each other, metallic intermediate plates interposed between adjacent impedances and in electrical contact therewith, and concavo-convex depressions formed in said plates and arranged with the concave parts in each plate opposed to the concave parts in the next adjacent plate and said concave parts receiving and making electrical contact with the said impedances and the said plates being so disposed in the stack in angular relation with respect to each other that the convex part of a depression which forms, with its concave part, the seat for an impedance unit, is axially separated from the convex part of the next succeeding impedance unit seating depression in the stack device by at least one intermediate plate.

2. A device according to claim 1, in Which the individual metallic intermediate plates are all alike 3. A device according to claim 1 in which the impedance seating depressions in one plate are symmetrically located with respect to a line in the plane of the plate and in which symmetrically located depressions have the same dimensions but opposite directions with respect to said plane.

References Cited in the file of this patent UNITED STATES PATENTS 2,005,986 Behr June 25, 1935 2,226,745 Schrack Dec. 31, 1940 2,324,108 Pyk July 13, 1943 2,444,037 Fritschi June 29, 1948 2,474,988 Sargrove July 5, 1949 2,495,339 Markowitz Jan. 24, 1950 2,615,145 Rydbeck Oct. 21, 1952 

